1. Field of the Invention
This invention generally relates to the area of medicine in the surgical field. Containers are used in surgery for application tools for applying objects. Some containers are especially suitable for holding special objects, in particular hemostatic clamps. Hemostatic clamps are also referred to as ligature clamps. Ligature clamps are used to tie or clamp blood vessels during surgical procedures, and kept in containers. These containers usually consist of holders, cassettes or magazines. The invention relates to such a magazine.
2. Related Art
Ligature clamps have been used in surgery for many years. They serve two basic functions, specifically tying vessels, nerves or fluid-carrying vessels of the human body, or marking a special surgical site, typically the periphery of a tumor, for example, which can later be seen in an X-ray. The ligature clamps (hereinafter referred to as clamps) are available in three basic sizes-small, medium and large, as well as in two special sizes combination small/medium and impervious to X-rays. Clamps used early on were V-shaped. However, the disadvantage to clamps shaped like this is that they pressed the vessel away from the clamp or cut into the vessel instead of tying it off. This problem was resolved through the use of pre-shaped, horseshoe-shaped clamps that were described in U.S. Pat. Nos. 3,323,216 and 3,363,628 and are currently in general use. The horseshoe-shaped clamp consists of two essentially parallel legs, which initially fix the vessel between the ends when closed, thereby holding it between the actual ligature between the ends.
In a typical magazine for holding and providing clamps in the prior art, a plurality of side-by-side clamps, e.g., ten, are pressed onto a rigid middle beam or pillow block. The outer shape of the pillow block corresponds to the inner shape of the horseshoe-shaped clamps. However, the clamps are somewhat smaller than the pillow block, so that the contact pressure between the parallel legs of the clamp and the pillow blocks holds the clamps during transport and prevents the clamps from falling out of the magazine if the magazine is turned or dropped. But this contact pressure is associated with several disadvantages. First of all, the contact pressure makes it hard to grip the clamp via the clamping jaws or branches of an application tool, in particular the special forceps. Secondly, it makes removal a very unsafe process, even though the application tool has two branches that can move relative to each other, the free ends of which each carry longitudinal grooves on the facing sides that run parallel to the branches and are open relative to the opposing branch. Application tools with a narrow clamping jaw width make it more difficult to grip the clamp, especially since the clamp already tightly abuts the pillow block, and therefore cannot be compressed. This significantly increases the friction between the application tool and the clamp, and metal might be shaved off the clamp. If the clamping jaws of the application tool are too wide, the clamp is sometimes not reliably gripped by the clamping jaws after removed from the magazine. As a result, the clamp might slip from the operating position inside the application tool or fall out of the application tool. Another disadvantage is that the contact tension makes it difficult to remove the clamp from the holding device of the magazine. The tight abutment between the clamp and pillow block generates significant friction between the pillow block and clamp, and the relatively small magazine must be held to enable removal. The required handling of the clamp and magazine is associated with additional disadvantages.
Further developments in prior art are intended to eliminate the above disadvantages. For example, U.S. Pat. No. 4,936,447 discloses a cassette for holding ligature clamps, in which the downwardly open end of the ligature clamps is plugged into a free compartment via a nose saddle, and both sides of its outer contour are held by a respective elastic holding device provided with a notch at the end. The holding device is designed with a special insert, which must additionally be connected with the basic body of the cassette. The notches on the holding device must reliably grip the ligature clamps, but easily release them again during removal by means of an application tool provided for this purpose. In the known cassette, the holding devices must be manufactured to exacting tolerances with respect to dimensions and resilience. They are also only suitable for mounting a single type of ligature clamp. Even if this magazine embodiment makes it possible to eliminate the aforementioned friction disadvantages, there remains the problem that the application tool and retaining straps disrupt each other, since these abut the arms of the clamps, which happen to form the areas into which the forceps reaches. This is the cause of disruptions. Another serious disadvantage to this cassette is that it has no guide for the application tool for removing the ligature clamps. Therefore, disadvantages are associated with handling when gripping the ligature clamps, i.e., the ligature clamp is not optimally situated in the application tool, so that mistakes can be encountered when tying off the vessels.
In the magazine described in WO 98/05260 A1 and the publications cited therein, each clamp sits astride a fixed element (reverse position with “U” turned upside down) with a complementary shape, which is seamed by a pair of massive transverse walls used to hold the clamps. The clamps incorporated in such a magazine are in part very small, e.g., the dimensions measure on the order of 1.5 mm, making it extremely difficult to handle the clamps. In the known magazines, the clamps are held in such a way that a forceps-like application tool can grasp the clamps when inserted into a magazine, and then pull them out of the magazine. The disadvantage to known magazines here is that the clamps are fixed laterally by elastically resilient clamping elements, which only abut the middle area of the web, and are lifted during the insertion of an application tool. Therefore, the clamps might become tilted or even jammed in the magazine while inserting the application tool, then making it impossible to introduce the clamp into the application tool in the manner envisaged.
Another problem is encountered in holding devices in clamp magazines according to prior art. In order to ensure that the application tool encompasses the clamps, the clamping jaws of the application tool must be stronger than the clamps. To allow the application tool to reach into the clamp compartment, this compartment must therefore be wider than the clamp. As a result of the wider clamp, the clamp can be varyingly positioned in the compartment as the application tool enters, and not be centered, so that the clamp is not gripped precisely by the middle of the application tool. A clamp not correctly gripped by the clamping jaws of the application tool can cause the clamp to close unevenly. The principle for removing the clamps from a magazine is identical for all known clamp sizes. The magazines for the varying clamp sizes are color-labeled for differentiation purposes. For example, the magazine accompanying the small clamp size is yellow, while it is blue for medium and orange for large.
There is a need therefore, for an inexpensive container with a simple functional geometry to hold hemostatic clamps, with elevated demands on safe storage and removal, and hence on tying off vessels, exhibiting a structural shape suitable for reliably removing clamps via a surgical instrument.